- Where does cellular respiration primarily occur in eukaryotic cells? a) Nucleus
b) Mitochondria
c) Cytoplasm
d) Ribosomes
Answer: b) Mitochondria - Which part of the mitochondrion is responsible for the electron transport chain? a) Outer membrane
b) Inner membrane
c) Matrix
d) Cristae
Answer: b) Inner membrane - Which molecule is produced as a result of the mitochondrial electron transport chain? a) Oxygen
b) ATP
c) Glucose
d) NADH
Answer: b) ATP - What is the primary function of mitochondria in cellular respiration? a) Synthesize proteins
b) Produce ATP
c) Store genetic information
d) Break down glucose
Answer: b) Produce ATP - Which process occurs inside the mitochondrial matrix? a) Glycolysis
b) Krebs cycle
c) Electron transport chain
d) Phosphorylation
Answer: b) Krebs cycle - During aerobic respiration, oxygen is used in which part of the mitochondrion? a) Matrix
b) Inner membrane
c) Outer membrane
d) Cristae
Answer: b) Inner membrane - Which molecule donates electrons to the electron transport chain in mitochondria? a) ATP
b) NADH
c) Glucose
d) Oxygen
Answer: b) NADH - What is the final electron acceptor in the mitochondrial electron transport chain? a) Water
b) Glucose
c) Oxygen
d) NADH
Answer: c) Oxygen - Which energy carrier is produced by the mitochondrial Krebs cycle? a) NADH
b) ATP
c) FADH2
d) All of the above
Answer: d) All of the above - Which of the following is NOT a product of cellular respiration in the mitochondria? a) Water
b) Oxygen
c) ATP
d) Carbon dioxide
Answer: b) Oxygen - How many ATP molecules are produced by the complete oxidation of one glucose molecule in the mitochondria? a) 2
b) 18
c) 32-34
d) 50
Answer: c) 32-34 - What is the role of the cristae in mitochondria? a) Storage of ATP
b) Increase surface area for ATP production
c) Contain DNA
d) Synthesis of glucose
Answer: b) Increase surface area for ATP production - In which mitochondrial compartment is the Krebs cycle located? a) Inner membrane
b) Matrix
c) Outer membrane
d) Cytoplasm
Answer: b) Matrix - Which molecule is synthesized during oxidative phosphorylation in the mitochondria? a) NADH
b) ATP
c) CO2
d) Glucose
Answer: b) ATP - Which molecule is NOT involved in the mitochondrial electron transport chain? a) NADH
b) Oxygen
c) Glucose
d) FADH2
Answer: c) Glucose - What happens to the electrons as they pass through the mitochondrial electron transport chain? a) They are absorbed by glucose molecules
b) They release energy used to pump protons
c) They are stored in ATP
d) They are combined with oxygen to form glucose
Answer: b) They release energy used to pump protons - Which of the following describes the proton gradient formed in mitochondria during cellular respiration? a) Protons move from the matrix to the outer mitochondrial membrane
b) Protons move from the outer mitochondrial membrane to the matrix
c) Protons move from the cytoplasm into the mitochondria
d) Protons are released from glucose molecules
Answer: a) Protons move from the matrix to the outer mitochondrial membrane - What is the main byproduct of mitochondrial cellular respiration? a) Glucose
b) Oxygen
c) Carbon dioxide
d) Nitrogen
Answer: c) Carbon dioxide - Which of the following statements about mitochondria is correct? a) They are involved only in anaerobic respiration
b) They have their own DNA and ribosomes
c) They contain no inner membranes
d) They perform protein synthesis in the cytoplasm
Answer: b) They have their own DNA and ribosomes - Which of the following is the correct sequence of events during aerobic respiration in mitochondria? a) Glycolysis → Krebs cycle → Electron transport chain
b) Krebs cycle → Glycolysis → Electron transport chain
c) Glycolysis → Electron transport chain → Krebs cycle
d) Glycolysis → Electron transport chain → Oxygen uptake
Answer: a) Glycolysis → Krebs cycle → Electron transport chain - What is the role of ATP synthase in mitochondria? a) It produces glucose from carbon dioxide
b) It transports protons across the inner mitochondrial membrane
c) It synthesizes ATP from ADP and inorganic phosphate
d) It converts NADH into NAD+
Answer: c) It synthesizes ATP from ADP and inorganic phosphate - In which part of cellular respiration does the mitochondrial matrix play a role? a) Glycolysis
b) Krebs cycle
c) Electron transport chain
d) All of the above
Answer: b) Krebs cycle - What is the source of energy that powers the electron transport chain in mitochondria? a) Glucose
b) ATP
c) NADH and FADH2
d) Oxygen
Answer: c) NADH and FADH2 - Which statement about the mitochondrial inner membrane is correct? a) It is permeable to all substances
b) It contains the enzymes for the Krebs cycle
c) It contains the enzymes for the electron transport chain
d) It is involved only in the transport of oxygen
Answer: c) It contains the enzymes for the electron transport chain - Which molecule is used by mitochondria as an energy source for ATP production? a) Glucose
b) Pyruvate
c) NADH
d) Oxygen
Answer: c) NADH - During cellular respiration, how is ATP produced in the mitochondria? a) By substrate-level phosphorylation
b) By oxidative phosphorylation
c) By glycolysis
d) By fermentation
Answer: b) By oxidative phosphorylation - What is the function of NADH and FADH2 in mitochondrial respiration? a) To act as final electron acceptors
b) To donate electrons to the electron transport chain
c) To transport protons across the inner membrane
d) To break down glucose
Answer: b) To donate electrons to the electron transport chain - Which of the following is produced in the Krebs cycle inside mitochondria? a) Pyruvate
b) NADH, FADH2, and ATP
c) Oxygen
d) Glucose
Answer: b) NADH, FADH2, and ATP - How does the mitochondrial membrane contribute to ATP production? a) By breaking down glucose molecules
b) By providing a site for the electron transport chain and ATP synthesis
c) By storing glucose molecules
d) By producing oxygen
Answer: b) By providing a site for the electron transport chain and ATP synthesis - What is the importance of the proton gradient in mitochondria during cellular respiration? a) It helps in the formation of glucose
b) It drives the synthesis of ATP
c) It transports NADH
d) It consumes oxygen
Answer: b) It drives the synthesis of ATP
These MCQs cover key aspects of the mitochondria’s role in cellular respiration, focusing on the processes involved, the locations, and the important molecules that contribute to energy production in the cell.